The Jobo photoGPS, also known as the Geotate Kato, lies part way between the stand-alone devices and the GP-1. It too is attached to the camera via the flash hot-shoe, but there is no direct data or power connection. Instead the device simply uses the hot-shoe trigger circuit to register when a photo is taken, and it simultaneously records the GPS location to its internal memory.
Later, when the photos are downloaded onto a computer the device is connected as well using USB, and the supplied photoGPS software compares and matches the recorded locations with the photos and adds the GPS co-ordinates to the EXIF data. The device runs on internal rechargeable batteries, and is charged via USB. Since it isn't running continuously battery duration is excellent. After a single charge the photoGPS was still operating several days later.
The photoGPS was also extremely quick to operate, taking just a couple of seconds to record a satellite signal. It was also the most consistently accurate of the five devices. Although it did fail to register a signal on one or two occasions, the rest of the time it was never more than a few meters from the exact spot. The only problem with the Jobo unit is its lousy hot-shoe adaptor, which is very loose and keeps slipping out of the shoe. It actually fell off the camera altogether a couple of times.
The Nikon P6000 is unique, because the GPS receiver is built into the camera. Once activated it remains running, and will place additional strain on the camera's battery, but like the GP-1 it does add GPS location data directly to the photos as they are taken. When I first reviewed the P6000 back in November the GPS worked perfectly well, reliably finding a strong signal and proving to be very accurate.
However when I came to use it for this trip it refused to find a signal at all, even when out in the countryside away from any possible obstructions or interference and under a relatively clear sky. It would still take pictures though, so I used it in conjunction with the Sony GPS unit. I took pictures for the ATP PhotoFinder using an Olympus compact that I will be reviewing next week.